Exhibit 32.1

CERTIFICATIONS OF PRINCIPAL EXECUTIVE OFFICER AND PRINCIPAL FINANCIAL OFFICER PURSUANT TO

18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report on Form 10-K of Codiak BioSciences, Inc. (the “Company”) for the year ended December 31, 2020 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that, to the best of their knowledge:

(1) the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: March 17, 2021	By:	/s/  DOUGLAS E. WILLIAMS
		Douglas E. Williams, Ph.D.
		Chief Executive Officer and President
		(Principal Executive Officer)
Date: March 17, 2021	By:	/s/  Linda C. Bain
		Linda C. Bain
		Chief Financial Officer
		(Principal Financial and Accounting Officer)